Walther feld



W'ALTHER FELD, OF HGNNINGEN-ON-THE-RHIN I, GERMANY, ASSIGNOR TO THE AMERICAN SUGAR REFINING COMPANY, OF NEXV YORK, N. Y.

PROCESS OF EXTRACTING SUGAR.

SPECIFICATION forming part of Letters Patent No. 592,517, dated October 26, 1897.

Application filed April 6, 1896. Serial N0. 586,435. (No specimens.)

To all whom it may concern: Water and barium hydrosulfid, which remains Be it known that I, \VALTHER FELD, asubdissolved in the Wastelye, according to the j ect of the German Emperor, residing at 11611- formula:

ningen-on-the-Rhine, Rhine Province, Ger- 5 man Empire, have invented certain new and useful Improvements in Processes of Extract This reaction takes place at all temperaing Sugar from Molasses and other Saccharine tures; but in order to accelerate it and have a Liquors by the Use of Barium Hydroxisulfid, complete precipitation of the saccharate it is of which the following is a specification. usual to heat the mixture above 140 Fahren- 10 It has heretofore been proposed to extract heit. By filtration through filter-presses and sugar from molasses or other saechariferous washing in the usual manner With pure ater liquors or juices by the use of barium comor asolution of barium saecharate containing pounds obtained from barium sulfid, (BaS.) about one and one-half per cent. of sugar the The barium sulfid is obtained by the reducbarium saccharate is separated from the waste 15 tion of commercial heavyrspar or barium sullye, which contains, besides the impurities fate with coal. It is the fact that when barium v originally present in the molasses, the Whole sulfid is leached systematically with hot Water quantity of barium hydrosulfid formed by the it gives a solution of barium hydroxisulfid, process, the excess of barium hydroxisulfid (BaS+H O:BaSHOl-l,) a substance which is used, and in lesser quantityvarious barium 20 very soluble in hot water, but will crystallize salts formed by the reaction of the barium easily from the solution if cooled down to hydroxisulfid upon the glucose and other imordinary atmospheric temperature. The aupurities of the molasses. thorities have nothitherto accepted this fact, The present invention consists in the herebut for the purposes of the present case the inafter-described method of extracting sugar 2 5 matter is not important, because any chemist from molasses or other sacchariferous liquors may theoretically explain the chemical reacby the use of barium compounds in such tions differently,and can, as hereinafter illusmanner as to effect the economical recovery trated, easily substitute other formulas for of the barium and sulfur employed. To this those herein given. In any event the practiend the Waste lye produced as heretofore set 30 cal result Will be the same. forth is saturated with carbonic acid, and the In the process of extracting sugar from mobarium compounds therein being thereby delasses as heretofore practiced a solution supcomposed all the sulfur from them is transposedly of barium sulfid, but actually conformed into gaseous hydrogen sulfid, While tainingabout thirty-five per cent. to forty per the insoluble barium carbonate remains sus- 35 cent. of barium hydroxisulfid and having a pended in the solution. The barium carbontemperature of about 1i5 Fahrenheit, is ate is separated from the Waste lye by settling thoroughly mixed with molasses or other 5210- or filtration. The latter is commonly effected co chariferous liquor in such proportions that by the use of the ordinary filter-presses. the mixture will contain for each one hun- The gaseous hydrogen sulfid is conducted to no dred parts of sugar about one hundred and a gasometer, from which it is transferred to fifteen parts of barium hydroxisulfid. Theoa furnace-chamber, wherein it is burned in retically this is about five per cent. more the usual Way with air in order to obtain the barium hydroxisulfid than is necessary; but sulfurous acid which it is thus made to yield it is advisable to use a small excess, and if the and which is available in the subsequent op- 4 5 molasses contains glucose or invert sugar a erations for recovering the barium employed. proportionallylargeramountmustbe added- The object of the subsequent steps of the thus for one part of glucose about one part of process is to transform into barium sulfite 10o barium hydroxisuliid. This excess reacts the various barium compounds which have upon the glucose and transforms it into babeen produced in the earlier stages of the 50 riuni compounds. By the reaction of thesugar process. To this end the barium carbonate the barium hydroxisulfid is split into barium gained by saturating the waste lye With caroxid, which, by combining with the sugar, bonic acid is mixed with Water and treated forms insoluble barium saceharate, and into either with sufficient sulfuric acid to transform the barium carbonate or other barium compounds present in it into barium sulfate, or it is treated with sufficient sulfurous acid to transform the barium carbonate or other barium compounds present in it into barium sulfite, the latter expedient being preferable, because of the supply of sulfurous acid yielded bythe burning of the hydrogen sulfid, as

described.

The barium saccharate which has been separated by filtration from the waste lye is then mixed with water or sugar liquors, and the mixture may then be treated with sulfuric acid or with sulfurous acid, whereby the barium saccharate will be decomposed into an aqueous solution of sugar and a barium sulfate or a barium sulfite, according to the acid employed. It is, however, preferable to treat the mixture of barium saccharate and water with a sufficient quantity of carbonic acid to decompose it into an aqueous solution of sugar and barium carbonate and tothen separate the barium carbonate from the sugar solution by filtration, after which the barium carbonate may either be mixed with water for subsequent treatment either with sulfuric acid or sulfurous acid for the purpose of transforming it into either a barium sulfate or a barium sulfite, as before described.

The resulting barium sulfate or barium sulfite, as the case may be, having been separated from the liquor in which it is contained by filtration, which is commonly effected by the use of the ordinary filter-presses, is then mixed with coal and heated in a reverberatory furnace in the ordinary manner and thereby transformed into barium sulfid,which is susceptible of being again used in the described manner to extract the sugar from another quantity of molasses or other sacchariferous liquor.

The novelty in this process resides, first, in the preliminary saturation of the waste lye with carbonic acid, whereby all the sulfur present is transformed into hydrogen sulfid, which by subsequent burning is made to yield sulfurous acid, and the subsequent treatment of the barium carbonate gained from the waste lye with sulfuric acid-or with sulfurous acid,

whereby the barium compounds present in it are transformed into salts-to wit, barium sulfate or barium sulfite, as the case may be either of which after separation from the lye by filtration is by reduction with coal transformed into barium sulfid, and, secondly, in the preliminary treatment of the aqueous mixture of barium saccharate with carbonic acid and the subsequent treatment of the resulting barium carbonate with sulfuric acid or sulfurous acid, whereby there is obtained a barium salt-to wit, barium sulfate or barium sulfite-either of which is susceptible of being reduced to barium sulfid by'burning with coal. After the barium saccharate is decomposed the resulting sugar solution is boiled down and the sugar crystallized out of it in the ordinary manner.

What is claimed as the invention is 1. In the processes of extracting sugar from molasses or other sacchariferous liquors by the use of barium compounds, the method of recovering from the waste lye the sulfur introduced in combination with barium, which consists in saturating the waste lye with carbonic acid, collecting the thereby-developed gaseous hydrogen sulfid and burning the same to sulfurous acid.

2. In processes of extracting sugar from molasses or other sacchariferous liquors by the use of barium compounds, the method of recovering the barium from the waste lye, which consists in first saturating the waste lye with carbonic acid andthereby forming barium carbonate; secondly, introducing a sulfur acid, thereby transforming the barium carbonate into a sulfur saltof barium; thirdly, separating the barium salt from the waste lye by filter-presses, and, finally,.reducing it in a reverberatory furnace to barium sulfid, substantially as described.

3. In processes of extracting sugar from molasses or other sacchariferous liquors by the use of barium compounds whereby barium saccharate is formed, the method of recovering the barium, which consists in first mixing the barium saccharate with water; secondly, saturating the mixture with carbonic acid, and thereby forming barium carbon- IIC scribed, whereby the constituents of the compounds employed are recovered in suitable form for repeated use, which consists in treating a saccharine liquor with barium hydroxisulfid, thus forming barium saccharate; separating the barium saccharate from the waste lye; treating the waste lye and the barium saccharate separately with carbonic acid; separating the pure-sugar solutionfrom the barium carbonate; burning the hydrogen sulfid obtained from the waste lye to sulfurous acid; treating the barium carbonate obtained from the saccharate and the barium carbonate present in the waste lye, with a sulfur acid and thereby forming a sulfur salt of barium, finally, reducing the resulting barium salt to barium sulfid, substantially as set forth.

In testimony whereof I have affixed my signature in presence of two witnesses.

VVALTHER FELD. 

